This collaborative project will collect arteries and risk factor data from 1,400 young persons 15-34 years of age who die from trauma and are autopsied in medical examiners' laboratories. The data will be analyzed to determine the associations of the risk factors for adult atherosclerotic disease with the various lesions of atherosclerosis that appear during this age period. These cases will supplement the 1,800 cases that are being collected in the ongoing multicenter cooperative study "Pathobiological Determinants of Atherosclerosis in Youth" (PDAY). The major purposes of the study are to: 1) obtain an adequate number of cases of women; 2) increase the power of the study to detect associations of risk factors with raised lesions which begin to appear in this age group; and 3) increase the power to detect genetic effects on atherosclerosis. Aortic and coronary artery lesions are measured by visual estimation and by gross and histologic morphometry using computerized image analysis. Risk factor measurements include cholesterol and lipoprotein cholesterol concentration in post mortem serum; thiocyanate in post mortem serum as a marker for smoking; blood pressure by wall thickness of renal arteries and arterioles; and DNA polymorphisms by analysis of liver DNA. Collection of cases is performed by participating centers in cooperation with local medical examiners. Processing of arteries, blood, liver, and other tissue is carried out in central laboratories, and data are managed by a statistical center. The Laboratory of Vascular Diseases (LVD) will function as the Morphometry Central Laboratory for the study. LVD will conduct quantitative morphometric analysis on all macroscopic (approximately 5,700) and microscopic (approximately 14,000) images of arterial tissue entered into the study. These analyses will employ modem techniques of image processing and will result in the production of both tabular and two-dimensional data. For the macroscopic studies of the thoracic and abdominal aorta and right coronary artery, tabular data of percentage surface area of the entire vessel segment, and also for smaller, more localized regions, for sudanophilic, raised and calcified lesions will be calculated and correlated with risk factor data (e.g., LDL cholesterol; Apo A, Apo B, LP(a); smoking; genetic phenotype, etc.). Similarly, two-dimensional probability-of-occurrence maps will be produced for subgroups (e.g., LDL < 130 mg/dl vs. LDL > 130 mg/dl) of these same risk factors. For the microscopic studies of sections from the thoracic and abdominal aorta and right and left anterior descending coronary arteries, tabular data of geometric parameters (e.g., intimal and medial thickness and area; lumen area, shape indices, ratios, etc.), and compositional parameters (e.g., area and percentage of area Oil Red "O" (ORO) positive, etc.) will be calculated and correlated with risk factor data. Similarly, two-dimensional mean arterial geometric form and probability- of-occurrence (e.g., ORO) will be produced for specific risk factor subgroups.